Compensating precision brush holder



Sept. 8, 1942; A. o; BELL ETAL 3 COMPENSATING PRECISION BRUSH HOLDER Filed Au 1, 1940' 2 Sheets-Sheet 1 Albert avawwb Sept. 8, 1942'. A. o. BELL ETAL COMPENSATING PRECISION BRUSH HOLDER 2 Sheets-Sheet? Filed Aug. 1, 1940 Albert ols'ea f Jere @Z'EZ Patented Sept. 8, 1942 'COMPENSATING PRECISION BRUSH HOLDER Albert-0. Bell and Leroy W. Vinal, Leominster, -Mass.,- and William Penn-Gaskill Hall, Berwyn, Pa, 'ass'ignor' to E.'I. du Pont de Nemours & Company, Wilmington, Del., a corporation of Delaware Application August 1, 1940, Serial No. 349,322

16 Claims.

This invention relates'to compensating precision brush holders and clamps for bristling machines, the holder being used to clamp'and' position the brush blanks for the drilling and bristle setting operations.

Objects of the invention include the "provision of-a new and improved brush-holder in which thebrush blanks will be held precisely in a desiredposition so that the bristles will be inserted toa-n equal extent in eachblank regardless of variations of the thickness of the blanks; the provision of-a brush holder for clamping 'a plurality of brush blanks in whichthe blanks may beheld individuallyor in pairs to compensate for any irregularities in the thickness of the blanks; the provision of a brush-holder having means to locate the faces of the blanks into which the bristles are to beset in predeterminedpositionso that each blank is positioned in the holder by its bristle receiving face, thus, regardless of irregularitiesof the thickness of the blanks-the brush drill and setting mechanism willalways penetrate each blank tothe same degree, due-to the structure of the holder; the provision of a compensating precision brush holder having a plurality of depressions or pockets inits upper surface for the reception of the brush blanks, there being plates curved to fit the faces of the blanks attached-to the holder and slightly overlying the depressions or pockets at the peripheries of theblan'k -to act as'limiting meansythe provision of individual means urging the blanks upwardly against the plates on the holder to clamp the same in correct position in the holder; the provision of means to 'sirnultaneously release the brush blanks from the means urging them against the limiting plates; and the provision of 'a new and improved brush holder for bristling machines which holds each brush precisely in-desired position and which compensates for variations in the thickness of the brush blanks.

Other objects and advantagesof the invention-will appear hereinafter.

Reference ist'o be had to the accompanying drawings, in which Fig. lis a plan'view' of one form which the improved brush holder may take, parts being broken away;

'Fig. 2 is a cross section on line 22 of'Fig. 1;

Fig. 3 is a front elevation of the device of Fig. 1, with parts broken away;

Fig. 4 is a plan view of another form'of improved brush hol'den parts-being broken away in this figure;

Fig. 5is a section on line5-5 ofFi'g. '4, showing the brush unclampedposition;

Fig. fi isa plan view of'the brush clamping wedge; v

Fig. 7 is a side elevation of the'w'edge of Fig. 6;

Fig. 8 is a plan view of a brush clamping element;

Fig. 9 is a side view of Fig. 8;

Fig. 10 is a front viewof Fig. 9, looking in the direction of arrow H]; and l Fig. 11 is a view similar to Fig. 5 but showing the brush clamped.

Heretofore brush blanks have-beenlocated in brush holders for the drilling and setting operations of the same by means of therear face of the brushblank so that variations in the thickness of the'bla-nks would cause a thicker blank to have its bristle receiving face positioned above the corresponding face of a thinner blankv This, of course, results in a shorter or deeper penetration of the drill and of the bristle tuft-and this in turn results in non-uniform brushes; i. e., brushes from which the bristles extend in'varying degrees. The present invention overcomes this objection to the prior art devices by positioning the blank in the holder 'by means of the face into which the bristles are to be set, so that the drill and the-tuft will penetrate the brush blank to the same degree in every case.

Themain body of the holder is indicated at H] and as is Well known in the'a-rt, the holder is provided with -gibs l2 which run-longitudinally of the holder and-areadapted to slidingly fit in ways I4 on a slide IS. The holder 16 is traveled longitudinally in the ways M by means of a screw, not shown, working irra half-nut IE on the holder. Adjacent one longitudinal edge of theholder, there is a-series of spaced bars 26 which are arranged transversely of the holder as shown. The bars 26 may be spaced so as to be used to laterally locate andguide the widest part ofthe brush heads as at 28, and to provide'depressions or pockets 29 therebetween to accommodate the same. Anendbar 30 which is a fraction ofthe width of the bars 26 but is used for the same purpose is provided at each end of the holder. as at 3| to provide handle supports, if convenient and desired. g

At the longitudinal edge of the holder, the spaced bars 26 merge into and may be integral with a longitudinal bar 32. Also, it is to be noted that the bars 26 have tapered side surfaces to substantially contact and locate the sides of the brush heads as at 34 and bar'32 may be shaped to correspond to" the curved ends of the brushes "as at 36. Thus'it will be seen that the brush heads are well located as regards their lateral edges and the spaces between the bars 26 provide depressions or pockets '29 lll'WhlCl'l the heads of the brushes are located and precisely 'posi- V tioned. 1 1

The general efiect of bars ZS-and 32,' which maybe and areshownas integral, is that of a comb, of which bar'32 is the back and bars 26 V 7 Bars 26-may be connected 7 are the teeth, the latter having tapering sides and curved roots to fit the brush heads. The comb is secured to the holder by bolts 38, so as to be rigidly fixed thereto.

The tops of bars 26 are accurately milled out to conform to the curves of the brush head faces which are to be bristled, and thin plates 49, also curved, are secured to the bars by screws 42. The plates are tapered to conform to bars 26 and to the brush heads, but are wider than the bars, and therefore slightly overlie the edges of the depressions or pockets which accommodate the brush heads. The plates are here illustrated as separate, but they could also be made in the form of an integral comb, like bars 26 and 32. Half plates 44 are used for end bars 30, and these plates also extend slightly over the adjacent pocket edge.

It will be seen from Figs. 1 to 3 that plates 46 provide peripheral brush head locating means, against the undersides of which the heads are adapted to be urged, to thereby locate each brush head with its bristle receiving face in exactly the same vertical position as all other brushes. However, the plates 40 are made so as to accomplish the locating function while still providing access of the drill and bristle needle to they brush face. It is to be undertsood that plates 40 and pockets 29 may be of any shape to conform to the particular brush being processed.

Referring to Fig. 2, the pockets 29 are shown to be undercut as at 46, and bars 26 are slotted (see the broken lines, Fig. l), to receive and position bent plate springs 48, so that each spring resiliently urges a pair of brush blanks upwardly against corresponding plates 40. Springs 48 are arranged to press upwardly against abutment pieces 50, each of which are of a size to fit in the undercut portions 46, and to engage a pair of brushes, these pieces being shaped on their top surfaces to fit the particular form of the brush heads. A cushioning pad 52 of rubber is interposed between a thin metal strip 55 and the abutment piece 50, and the latter, the pad, and the strip are all riveted together as shown. Wear plates 53 are provided for the ends of the springs 48.

Buttons 54 are provided to work through alternate plates 40 and bars 26, these buttons being located in the slotted bars so as to extend therethru and impinge on the abutment pieces at their centers. The buttons have shoulders 56 to prevent their being pushed out of the plates 40 by the springs 48, and also to insure positive downward movement of the combined abutment piece, pad, and strip 55. An operating bar 58 having a series of bosses 60 is provided to operate all buttons 54 simultaneously, and bar 58 may be actuated by a foot treadle or other convenient means, not shown, to leave the operators hands free.

From the explanation, it Will be clear that a compensating clamp of great precision has been provided, since when the buttons are depressed by bar 58, the springs 48 are flattened out and a series of blanks may be placed by hand in the holder. The tapering sides of the pockets 29 guide the brushes to correct horizontal position, and when bar 58 is released, springs 48 will resiliently urge the blanks against the plates 40, whereby the top face of each blank will be verti-- cally equal to each other blank, and the drill and bristle needle will therefore place the bristles to equal depths in the brush, regardless of any variations in the thickness of the blanks.

Figs. 4-10 disclose a modification of the invention, in which a holder 60 is provided with a grid-like member 62. This member is formed with alternate depressions or pockets 64, for reception of the brush handles, and guiding or locating ribs 66. A side bar 68 for the ends of the brush heads corresponds to bar 32 in Fig. 1, and locating top plates 10 correspond to plates 40. Below the pockets 64, there are thru slots 12, the bottom surfaces of which comprise the top of the holder 68, and slots 12 penetrate into a wider cut-out 14, at the point of location for the brush heads, as shown in Fig, 5. In each cut out '14, there is a freely vertically movable brush head abutting element 16 having its top surface 18 curved to conform to the brush head. It will be noted that there is one such abutting element for each brush. Thru each slot 12 there extends a slidable rod having an enlarged head 82 mounting a top cam surface, and this cam is adapted to engage in a generally corresponding cam slot 84 in the element I6. Obviously, the rod 80 will force element 76 upwards to clamp the brush head against plates 10 upon sliding it to the left in Fig. 5, under influence of the spring 85, which constantly urges the rod to brush clamping position. It will be noted that the cam on the head 82 is straight, and this cam forces the element into clamping position, see Fig. 11, by its sliding contact with the bottom edge of the surface 84.

Each rod may be equipped with a lug 86 by which all the rods may be retracted simultaneously thru a bar 88, operated by a crank or foot lever not shown. Cooperating shoulders 90, 92 provide a stop for the rods, and elements 16 may be provided with bores 94 for the reception of springs 96 which will force the elements down from the brushes upon retraction of rods 80.

The modified form of the invention as disclosed in Figs. 4 to 10 provides a compensating brush clamp of the nature of the form shown in Figs. 1 to 3, but does away with the springs 48 and at the same time has a more positive brush holding means, as well as an individual clamp for each brush, so that individual brush variations will be accounted for. Also, any individual rod 80 may be separately retracted for inspection of a single blank. However, the basic conception of both forms is the same; i. e., the provision of a brush holder in which all the brush faces to be bristled are always located at the same height, so that the bristles will extend from such faces uniformly, and in which all the clamping means may be released simultaneously, although the individual brushes are clamped singly or in pairs.

Having thus described our invention and the advantages thereof, we do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what we claim is:

1. In a device of the class described, a compensating brush holder for a bristling machine, comprising limiting means extending a substantial distance about the periphery of the brush area to be bristled, and resilient means to urge the brush against said limiting means to clamp the same thereagainst.

2. In a device of the class described, a compensating holder for a brush blank having a face which is to be bristled, means on the holder to receive the blank, stop means adapted to engage said face to locate the same in the holder by the face to be bristled, regardless of the thickness of the blank, resilient means to urge said brush against said locating means, and means operable to retract said resilient means to release the blank.

3. In a device of the class described, a compensating holder for a brush blank having a face which is to be bristled, means on the holder to receive the blank, stop means adapted to be engaged by said face to locate the same in the holder by the face to be bristled, regardless of the thickness of the blank, means to urge said brush against said locating means, said urging means comprising a spring located in said blank receiving means, and means to tension said spring to release said blank.

4. In a device of the class described, a compensating brush holder for a bristling machine, said holder having separate means to receive a plurality of brush blanks, stop means adapted to engage and to locate said blanks in said means by the faces to be bristled, resilient means to urge said blanks into clamped relation with said locating means, and means to simultaneously retract said urging means to release said blanks.

5. In a device of the class described, a compensating brush holder for a bristling machine, said holder having a plurality of brush blank receiving pockets, means adjacent the pockets to locate each brush, resilient means to urge said blanks against said locating means in pairs, and means to release said blanks in such pairs from said urging means.

6. In a device of the class described, a compensating holder for a brush blank having a side to be operated upon, comprising a support, a pocket in the support for receiving a blank, a freely slidably element also in said pocket, means to urge said element against the opposite side of said blank, and stop means for said first named side of said blank, against which said urging mean is adapted to hold the same, said urging means always being efiective in its holding function regardless of variations in thickness of individual blanks.

7. In a device of the class described, a holder for brush blanks, a series of pockets in said holder, each pocket adapted to receive a blank, separate means in each pocket to individually clamp said blanks, springs to urge said separate means to clamping position, and a single means to simultaneously retract said springs to' release said separate means.

8. In a device of the class described, a holder for a blank to be operated upon, and comprising a support, a pocket in said support adapted to receive a blank and a movable clamping element, a cam surface on said element, a slidable rod having a cooperating cam surface, stop means on the support, said rod being adapted to move said element to clamp the blank between said stop means and said element, upon sliding movement thereof in one direction, yielding means efiective to normally move said rod in said direction, and positive means to retract said rod.

9. In a device of the class described, a compensating holder for a brush blank comprising a support, means forming an open pocket or the like in said support, stop means adjacent the open portion of the pocket, an element located in said pocket between the bottom thereof and said stop means, said element being slidable in said pocket to and from a position adjacent said stop means, and a spring tensioned between the bottom of the pocket and said slidable element so as to normally yieldingly urge said element toward said stop means, whereby said brush blank may be clamped in said stop means.

10. A device as recited in claim 9 including means operable from the exterior of the pocket to move said element away from the stop means against the action of the spring to release said brush blank.

11. In a device of the class described, a compensating holder for brush blanks comprising a support, means forming a plurality of open pockets in said support, stop means adjacent the open sides of the individual pockets, an element in each pocket adapted for movement to and from positions adjacent said stop means, a slidable rod having a cam engaging each element to move it toward its stop means, a separate spring to urge each of said rods to element-moving position, and a single means for retracting all said rods against the action of said springs.

12. A device as recited in claim 8 including light resilient means normally urging said clamping elements away from said stop means.

13. In a device of the class described, a compensating brush holder for a bristling machine, comprising means forming a pocket in the holder, limiting means extending about a part of the periphery of the pocket and overlying the same at its edges to outline the brush area to be bristled, and resilient means adapted to urge a brush block against said limiting means to clamp the block thereagainst.

14. In a device of the class described, a compensating brush block holder comprising a body, means forming an open pocket in said body for reception of a brush block, limiting means at points along the edges of the pocket and extending slightly thereover into the area of the pocket, resilient means adapted to urge a brush block in the pocket against said limiting means to clamp the brush block, and means for retracting said resilient means for release of said brush block.

15. In a device of the class described, a compensating brush holder for a bristling machine comprising means forming a pocket in said holder, brush block limiting means extending a substantial distance about the edges of said pocket and partially overlying the same to provide a clamping member for a brush block in the pocket, an element adapted to underlie a brush block in the pocket, said element being slidable in said pocket to provide a brush block clamping member to cooperate with said first named clamping member for clamping the brush block, and resilient means for urging said element in a direction towards said limiting means.

16. In a device of the class described, a compensating brush holder for a bristling machine comprising means adapted to receive a brush block, limiting means extending a substantial distance about the periphery of the brush area to be bristled, said limiting means being mounted on said first named means and located to engage edges of a brush block in said first named means, an element in said first named means adapted for movement to clamp the brush block against said limiting means, and resilient means adapted for urging said element in a direction to accomplish the brush block clamping action.

WILLIAM PENN-GASKILL HALL.

LEROY W. VINAL.

ALBERT O. BELL. 

